Walling began her career in 1919 after graduating from Burnley Horticultural College. She sought to achieve a unity between house and garden, and was influenced by Italian and Spanish gardens in her use of pergolas, walls, steps and paths.
She created a picturesque village at Bickleigh Vale in Mooroolbark in the 1920s, building some of the cottages with her own hands. In the 1950s she changed her emphasis towards native plants, promoting their use in the suburban garden, and wrote passionately about conservation of the natural environment.
Walling designed and constructed many well-known private gardens in Australia in the mid-20th century, for clients such as Dame Nellie Melba, Dame Elisabeth Murdoch and Sir Frank Packer.
Walling was a prolific writer. Four of her books were published in her lifetime and a fifth posthumously in 1984. She contributed hundreds of articles to The Australian Home Beautiful from 1925 to 1947 and left several unpublished manuscripts, now held in the Library’s manuscript collection. One of these, 'The happiest days of my life', is a personal account of the building of her beach house above the Great Ocean Road near Lorne.
The Edna Walling website created by Tantamount Productions, the ABC and State Library Victoria was launched in 2001 and for many years was the ABC’s most visited website.